boards: xtensa: intel_s1000_crb: set USB_DFU_MAX_XFER_SIZE to 4096
boards: xtensa: intel_s1000_crb: set USB_DFU_MAX_XFER_SIZE to 4096

patch set the config USB_DFU_MAX_XFER_SIZE to 4096. This will
reduce the time required for flashing.

Signed-off-by: Savinay Dharmappa <b9bdbfc60b49ae384b99e3313b3f20d055baeacb@intel.com>

punitvara/zephyr,punitvara/zephyr,explora26/zephyr,finikorg/zephyr,galak/zephyr,galak/zephyr,GiulianoFranchetto/zephyr,punitvara/zephyr,explora26/zephyr,nashif/zephyr,nashif/zephyr,punitvara/zephyr,GiulianoFranchetto/zephyr,ldts/zephyr,GiulianoFranchetto/zephyr,Vudentz/zephyr,ldts/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,nashif/zephyr,explora26/zephyr,galak/zephyr,Vudentz/zephyr,Vudentz/zephyr,zephyrproject-rtos/zephyr,explora26/zephyr,galak/zephyr,galak/zephyr,finikorg/zephyr,ldts/zephyr,ldts/zephyr,explora26/zephyr,zephyrproject-rtos/zephyr,GiulianoFranchetto/zephyr,Vudentz/zephyr,ldts/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,punitvara/zephyr,Vudentz/zephyr,Vudentz/zephyr,GiulianoFranchetto/zephyr,nashif/zephyr,nashif/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr